A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(M...A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(MAO)as a cocatalyst catalyzed the copolymerization of norbornene(N)and styrene(S)or para-chlorostyrene(CS)with high activity(up to 1070 kg·mol^-1·h^-1).The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content,affording high molecular weight copolymers with tunable CS content(0.57 mol%-11.7 mol%),in which the existence of CI group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked polymers.The linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers(COC).展开更多
Generation of multi-substituted pyrroles is accomplished through an unexpected iron(Ⅱ)-promoted reaction of N-arylprop-2-yn-1-imines with wate r.This transformation proceeds smoothly with excellent chemoselectivityan...Generation of multi-substituted pyrroles is accomplished through an unexpected iron(Ⅱ)-promoted reaction of N-arylprop-2-yn-1-imines with wate r.This transformation proceeds smoothly with excellent chemoselectivityand regioselectivity.A stoichiometric amount of Fe(OTf)_(2) is necessary for the succes s ful conversion.A Lewis acid-promoted tandem reaction pathway is proposed.展开更多
An efficient synthesis of 1,3-oxathiolane-2-imin derivatives is described via one-pot reaction between arylisothiocyanats, asymmetrically substituted oxiranes and catalytic amount of methanol.The mild reaction conditi...An efficient synthesis of 1,3-oxathiolane-2-imin derivatives is described via one-pot reaction between arylisothiocyanats, asymmetrically substituted oxiranes and catalytic amount of methanol.The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of this method.展开更多
基金the National Natural Science Foundation of China(No.21774018)the Fundamental Research Funds for the Central Universities(No.2232020A-05)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning.
文摘A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(MAO)as a cocatalyst catalyzed the copolymerization of norbornene(N)and styrene(S)or para-chlorostyrene(CS)with high activity(up to 1070 kg·mol^-1·h^-1).The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content,affording high molecular weight copolymers with tunable CS content(0.57 mol%-11.7 mol%),in which the existence of CI group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked polymers.The linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers(COC).
基金Financial support from the National Natural Science Foundation of China(Nos.21871053 and 21532001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)is gratefully acknowledged。
文摘Generation of multi-substituted pyrroles is accomplished through an unexpected iron(Ⅱ)-promoted reaction of N-arylprop-2-yn-1-imines with wate r.This transformation proceeds smoothly with excellent chemoselectivityand regioselectivity.A stoichiometric amount of Fe(OTf)_(2) is necessary for the succes s ful conversion.A Lewis acid-promoted tandem reaction pathway is proposed.
文摘An efficient synthesis of 1,3-oxathiolane-2-imin derivatives is described via one-pot reaction between arylisothiocyanats, asymmetrically substituted oxiranes and catalytic amount of methanol.The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of this method.
